Furnace and port construction



y 1930. G. L. DANFORI HQ JR 1,769,212

' FURNACE AND FORT CONSTRU G'I'ION I Filed Mal-ch15, 1922 g Z a hue/7W.-

amammzfz Patented July 1, 1930 UNITED sTATEs PATENT oFFIcE GEORGE L. DANFORTH, JR., OF CHICAGO, ILLINOIS, ASSIGNOR, BY MESNE ASSIGN- MENTS, TO OPEN HEARTH COMBUSTION COMPANY, OF CHICAGO, ILLINOIS, A COR- PORATION OF DELAWARE FURNACE AND PORT CONSTRUCTION Application filed March 15, 1922. Serial No. 544,047.

This invention relates to a new and. improved furnace and port COIlStI'llCtlOIl and more particularly to such a construction applied to metallurgical furnaces of the open hearth type.

through ports at one end of the furnace and the products of combustion are carried off through similar ports upon the opposite end of the furnace. The products of combustion serve to heat regenerative chambers which upon reversal serve to preheat the incomlng air or both the incoming air and the incoming fuel. Upon reversal of the furnace, the ports, which previously served to carry off the products of combustion, now serve to 1ntroduce the fuel and air, and the products of combustion pass out through the ports which previously served as the incoming ports. I

The volume of the products of combust on considerably exceeds the volume of the 1ncoming air and fuel. The size and design of the orts is, therefore,largely determlned by the necessity for carrying off the products of combustion. It is, however,'essent1al that the incoming air andffu'el be properly directed and intermixed so as to produce a relatively short flame and that the flame be prope'rly controlled. Where the ports serve both as incoming and outgoing ports,-1t has been impossible to entirely reconcile the difiering requirements of the incoming and outgoing ports.

Certain previous inventions as, for example, the patent to McKune, No. 1,339,855, issued May 11, 1920, have beendirected toward remedying these defects by the provision of additional channels which serve upon the outgoing end to aidin carrying ofi the products of combustion.

It is an object of the present-invention to provide in furnaces of this type, having a combined port for the introduction of'air and fuel, passages which communicate'both with the port and the furnace chamber and. means adapted to selectively interrupt cominnnt cation between the passages and the furnace chamber.

It is an additional object to provide in a construction of this character, passages which have openings directly associated with the furnace chamber, the openings being of a size adequate for carrying off the products of combustion.

It is a further object to provide these passages with means adapted to interrupt their communication with the furnace chamber so that they may serve upon the incoming end to introduce the air and to properly direct it into the combined air and fuel port.

It is also an object to provide a construction which is simple in design and which may be readily applied to existing installations.

Other and further objects will appear as'.

the description proceeds.

Broadly, my lnvention co-mprlses the provision 111 an open hearth furnace, having the combined air and fuel port, of air passages communicating with the combined air port and also with the furnace chamber, and means adapted to selectively interrupt communication between the passages and the furnace chamber. In the particular embodiments of which I have shown herein, the interrupting means consists of water-cooled dampers- I have illustrated a preferred embodiment of my invention in the accompanying drawings, in. which- Figure 1 is a vertical section showing one end of a furnace constructed according to the present invention;

Figure 2 is a horizontal section taken on line-2'2 of Figure 1 and Figure 3 is a transverse vertical section taken on line 3-3 of Figure 2.

As shown in the drawings, the fuel uptake 6 is directed at 7 to the rear of the combined air and fuel port 8. This port 8 isdirected into the end of the furnace chamber 9. It

gas port iscovered at 10 and that the combined port is covered at 11. The space 12 exists between these covering portions and the roof 13 of the end of the furnace.

As shown in Figures 2 and 3, the airuptakes 14 and 15 communicate with the combi'ned fuel and air port through transverse passages 16 and 17. The two air uptakes are provided with the dampers 18 and'19 respectively, which dampers operate on watercooled guide-ways 20. It is to be understood that the gas and air uptakes lead to suit able regenerative chambers which may be of any usual construction and which are, therefore, not shown. The opposite end of the furnace is identical with that which has been shown.

In the operation of the furnace, upon the.v incoming end, the dampers 18 and 19 are in the inward position and serve to block off the upper end of the air uptakes. The air coming up through the uptakes is directed by the dampers through the lateral passages 16 and 17, and the air streams there meet the gas stream which comes up the uptake 6 and is directed through the opening 7 into the rear of the combined port. The lateral air passages, as shown, are of greater height where they enter the combined port than is the entrance 7 through which the gas enters the ort. p The walls of the combined port converge toward each other so as to narrow the port toward the furnace proper. Air and gas arev properly intermingled in this port and. a relatively short, hot, effective flame is produced.

Upon the outgoing end, the dampers are drawn out and the products of combustion may directly enter the tops of the air uptakes. A portion of the products of combustion will enter the-combined air and fuel port and thus go downthe gas uptake and also pass through the lateral passages'lfi and 17. How-ever, the greater portionpf these gases will pass over the top of the port and over the lateral continuations of this top and will pass directly down the air uptakes. This provision of greater area directly in communication with the furnace chamber upon the outgoing end serves to easily carry off the products of combustion without the necessityfor forced draft means. It further permits the use of a relatively small incoming port properly designed to adequately mix the air and fuel and to efficiently direct and control the flame.

It is to be understood that the particular design of furnace shown is illustrative only and I reserve the right to make such changes and modifications as come within the spirit and scope of the appended claims.

I claim: I 1. In an open hearth furnace, a combine air and fuel port, an air passage communicating with a side of the combined port and with the furnace chamber, and means adapted to selectively interrupt communication between the air passage and furnace chamber.

2. In an open hearth furnace, a combined air and fuel port, an air passage communiing with the furnace chamber, a supplemental passage connecting the air passage and a lateral portion of the port, and a damper adapted to selectively close of! communication between the air passage and furnace chamber.

' 4. In an open hearth furnace, a combined air and fuel port, an air passage communicating with the furnace chamber, a diagonally extending supplemental passage connecting the air passage and a side of the port, and a damper located between the entrance of said supplemental diagonally extending passage into the air passage and the entrance of the air passage into the furnace chamber adapted to selectively close off communication between the air passage andfurnace chamber.

5. In an open hearth furnace, a combined air and fuel port, an air uptake communicating directly with "the furnace chamber, a diagonally extending passage connecting the air uptake with an intermediate portion of the port, and means in the air uptake above said diagonal passage adapted to selectively interrupt communication between the uptake and the furnace chamber.

7 6. In an open hearth furnace, a combined air and fuel port, an air uptake communicating directly with the furnace chamber, a

transverse passage connecting the air uptake with the port, and a horizontally operating damper in the air uptake above said transverse passage adapted'to selectively interrupt communication between the uptake and the furnace chamber.

7 In an open hearth furnace, a fuel uptake, an air uptake upon each side of the fuel uptake, a combined fuel and air port extending from the fuel uptake, and a diagonal passage connecting'each air'uptake to an intermediate portion of the port, the upper ends of the air uptakes being in direct communication? with the furnace chamber.

8. In an open hearth furnace, a fuel uptake, an air uptake upon each side of the fuel uptake, a combined fuel and air port extending from the fuel uptake, a, diagonal passage connecting each air uptake to an intermediate portion of the port, the upper ends of the air uptakes being in direct communication with thefurnace chamber, and means in each airuptake adapted to selectively direct air into said diagonal passages.

9. In an open hearth furnace, a fuel uptake, an air uptake upon each side of the fuel uptake, a combined fuel and air port extending from the fuel uptake, a diagonal passage connecting each air uptake an intermediate portion of the port, the upper ends of the air uptakes being in direct communication with w the furnace chamber, and a damper in each uptake adapted to selectively'closethe upper ends of said uptakes."

10. In an open hearth furnace,"a fuel up;

take, an air uptake upon each side of the fuel 7 uptake, a combined fuel and. air port extending from the fuel uptake, and a diagonal passage connecting each air uptake to an intermediate portion of the port, the entrance of the passages into the port extending the full depth of the port, the air uptakes' being in communication with the furnacechamber.

11. In an open hearth furnace, a fuel uptake, an air uptake upon each side of the fuel uptake, a combined fuel and air port, extending from the fuel uptake, and a diagonal passage connecting each air uptake to an intermediate portion of the p0rt, the' entrance of the passages into the port being of greater depth than the entrance of the fuel uptake into the port and extending higher than said latter entrance.

Signed at Chicago, Illinois, this 11th day of March, 1922.

GEORGE L. DANFORTH, JR. 

